I have an 09' TRD off road Double Cab with 50,000 miles on it. The previous owner did not have the TSB done so it has the original 3 leaf pack. I was looking at the packs today and it appears as if they have a negative arch. I am going to attempt to see if they will do the TSB out of warranty (I know my chances are slim and none) but when they most likely say no, what would my best option be? AAL or replace the entire pack? I have a topper on the bed and the truck sits pretty level and is even slightly nose high. I was thinking about doing 5100's all the way around with either the AAL or new leaf pack. I don't need the truck to sit level and wouldnt mind the stock look of it being slightly bed high. Thoughts??

Thanks for the info guys... I was planning on getting the 5100's all the way around. I don't need a 3 inch lift, 2 or 2.5 would be fine. What would be a good set of leaf springs to compliment the 5100's. The only ones I have seen are the Dakar OME. Any other options?

All- Pro has a replacement leaf pack that gets good rep here. They are currently on sale - 25% off. I just ordered a pair for my 05' Access 4X4 last night. My original spring pack looks a lot like yours...so I figured an AAL would not be enough to rid me of my sag. They are also making a beefier "expedition" leaf spring pack you might look into w/ a cap on back.http://www.allprooffroad.com/05tacomarearsuspension/05tacomaleafsprings

Thanks for the info guys. I am still a little confused as I am a "noob" to this stuff. I am looking to get around the same ride height as a truck with the TSB springs and an AAL. Something that will still be able to use the 5100 shocks. I am reading that the 5100's might be too short for the OME and the icon springs. Is that correct? I guess another option would be to find some TSB springs and just use those with the Billies...